Although annular pancreas is a congenital anomaly, it usually does not cause symptoms until adult life and may be found as an incidental autopsy finding. In a series of 58 cases collected by Giammattei,1 in 1955, only 10 (17%) caused obstruction during the first 10 days of life. In 1954, Farringer2 collected 14 cases in infants and children and added a 19-day-old case of his own. Because of the rarity of this condition as a cause of duodenal obstruction in the newborn, it was considered worth while to report three such cases seen by us during a two-month period.
The occurrence of annular pancreas can readily be related to its embryological development during the fourth week. Lecco's theory that adherence of the right ventral bud to its point of origin and its stretching to form an encircling piece of tissue at the time of rotation of the duodenum